How Did Cahokian Farmers Feed North America's Largest Indigenous City?

[wnylib]

1. I've always taken it as a given that

pre Columbisn Americans produced enough crops to support a city like Cahokia or the city would not have existed. But since the only domesticated animals the Native people of N. America had were dogs and turkeys, I wonder how they obtained animal products that they needed, e.g. skins,fur,hides, bones, sinew, and meat. Perhaps there were hunters in the outlying areas who carried on a regular trade with the city residents.